NAME

Net::DNS::SEC::Private - DNS SIG Private key object

SYNOPSIS

use Net::DNS::SEC::Private; my $private=Net::DNS::SEC::Private->new($keypath);

DESCRIPTION

Class containing a the private key as read from a dnssec-keygen generate zonefile. The class is written to be used only in the context of the Net::DNS::RR::SIG create method. This class is not designed to interact with any other system.

METHODS

new

$private->new("/home/foo/ Kexample.com.+001+11567.private")

Creator method. The argument is the full path to a private key generated by the BIND dnssec-keygen tool. Note that the filename contains information about the algorithm and keyid.

private

$private->private

Returns the private key material. This is either a Crypt::OpenSSL::RSA or Crypt::OpenSSL::DSA object. This is really only relevant to the Net::DNS::RR::SIG class.

algorithm, keytag, signame

$private->algorithm
$private->keytag
$private->signame

Returns components as determined from the filename and needed by Net::DNS::RR::RRSIG.

RSASHA1 specific helper functions

These functions may be usefull to read and transfer BIND private keys to and from X509 format.

new_rsa_private

Constructor method.

my $private=Net::DNS::SEC::Private->new_rsa_private($keyblob,$domain,$flag);

Creates a Net::DNS::SEC::Private object from the supplied string. For the object to be useful you will have to provide the "domain" name for which this key is to be used as the second argument and the flag (either 256 or 257 for a non SEP and a SEP key respectivly).

The string should include the -----BEGIN...----- and -----END...----- lines. The padding is set to PKCS1_OAEP, but can be changed with the use_xxx_padding methods

It is the same

dump_rsa_priv

my $bind_keyfilecontent=$private->dump_rsa_priv

Returns the content of a BIND private keyfile (Private-key-format: v1.2).

An empty string will be returned if not all parameters are available (please supply the author with example code if this ever happens).

dump_rsa_pub

my $bind_keyfilecontent=$private->dump_rsa_pub

Returns the publick key part of the DNSKEY RR.

Returns an empty string on failure.

dump_rsa_keytag

my $flags=257;   # SEP key.
my $keytag=$private->dump_rsa_keytag($flags);

This function will calculate the keytag assuming that key is a used with the RSASHA1 signing algorithm and with the DNSKEY flags as input.

The flags field may be needed in case it was not specified when the key was created. If the object allready knows it's flags vallue the input is ignored.

returns undefined on failure

dump_rsa_private_der

my $keyblob=$private->dump_rsa_privat_der

Return the DER-encoded PKCS1 representation of the private key. (Same format that can be read with the read_rsa_private method.)

generate_rsa

my $keypair=Net::DNS::SEC::Private->generate_rsa("example.com",$flag,1024,$random);
prin $newkey->dump_rsa_priv;
print $newkey->dump_rsa_pub();

Uses Crypt::OpenSSL::RSA generate_key to create a keypair.

First argument is the name of the key, the second argument is the flag field (take a value of 257 for Keysigning keys and a value of 256 for zone signing keys). The 3rd argument is the keysize.

If the 4th argument is defined it is passed to the Crypt::OpenSSL::Random::random_seed method (see Crypt::OpenSSL::RSA for details), not needed with a proper /dev/random.

Example

This is a code sniplet from the test script. First a new keypair is generated. An Net::DNS::RR object is created by constructing the resource record string - using the dump_rsa_pub() method.

Then a self signature over the public key is created and verified.

    my $newkey=Net::DNS::SEC::Private->generate_rsa("example.com",257,1024);
    my $tstpubkeyrr= Net::DNS::RR->new ($newkey->signame .
                                    "  IN DNSKEY 257 3 5 ".
				    $newkey->dump_rsa_pub());
    # flags not needed as argument for dump_rsa_keytag
    $ since they where set by generate_rsa

    is($tstpubkeyrr->keytag,$newkey->dump_rsa_keytag(),
                "Consistent keytag calculation");

    my $sigrr= create Net::DNS::RR::RRSIG([$tstpubkeyrr],$newkey);
    is ($sigrr->keytag,$tstpubkeyrr->keytag,
            "Consisted keytag in the created signature");;

    ok($sigrr->verify([$tstpubkeyrr],$tstpubkeyrr), 
             "Self verification consistent.");

COPYRIGHT

Copyright (c) 2002-2005 RIPE NCC. Author Olaf M. Kolkman <olaf@net-dns.org>

All Rights Reserved

Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation, and that the name of the author not be used in advertising or publicity pertaining to distribution of the software without specific, written prior permission.

THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS; IN NO EVENT SHALL AUTHOR BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

This code uses Crypt::OpenSSL which uses the openssl library

SEE ALSO

http://www.net-dns.org/

perl(1), Net::DNS, Net::DNS::RR::SIG, Crypt::OpenSSL::RSA,Crypt::OpenSSL::DSA, RFC 2435 Section 4, RFC 2931.